1. Field of the Invention
The present invention relates to a connector used for connecting wiring harnesses and more particularly to a connector structure having a terminal lock mounted to a connector housing to prevent a terminal lug inserted into the terminal accommodating chamber of the connector housing from slipping off backwardly.
2. Prior Art
A general practice of locking the terminal lug inserted into the terminal accommodating chamber in the connector housing is by forming a flexible engagement piece integral with the inner wall of the terminal accommodating chamber and then engaging the terminal lug inserted into the chamber with the flexible engagement piece to prevent the terminal lug from slipping off backwardly from the terminal accommodating chamber. In recent years, there has been proposed a structure in which a terminal lock is mounted to the rear part of the connector housing so that the terminal lock, either in combination with or in place of the flexible engagement piece, can reliably prevent the slip-off of the terminal lug.
In this structure, the terminal lock is coupled to the connector housing through a two-step coupling process, which involves a partial or half-coupled state that allows the terminal lug to be inserted into the terminal accommodating chamber and a full-coupled state that locks the terminal lug.
In FIG. 4, denoted a is a connector housing and b a terminal lock. The terminal lock b is shown half-coupled to the connector housing a (engagement mechanism of these two members are not shown).
Provided inside the connector housing a are a plurality of terminal accommodating chambers c, each of which is provided with a flexible engagement piece e that engages a terminal lug d as shown in FIG. 5. The terminal lock b is formed with insertion openings f corresponding to the terminal accommodating chambers c through which the terminal lugs d are inserted. The terminal lock b is also formed with terminal holding pieces g that are inserted into respective terminal accommodating chambers c.
In the above construction, as the terminal lugs d are inserted through the insertion openings f into the terminal accommodating chambers c, the advancing terminal lugs d deflect the terminal holding pieces g located in the insertion path, and further advances deflecting the flexible engagement pieces e. When the terminal lugs d are fully inserted, the terminal holding pieces g and the flexible engagement pieces e snap back to their original shapes.
However, this structure has drawbacks. That is, there is a gap between the terminal lock b and the connector housing a and since the terminal lug d easily inclines, pushed by the reactionary force of the terminal holding piece g, as it passes through the terminal lock b, the front end d.sub.1 of the terminal lug d being inserted abuts against the rear end a.sub.1 of the connector housing a. As a result, the terminal insertion work cannot be performed smoothly.